The government's chosen mechanism to increase the state pension age for women could have breached the UK's international legal obligations under the United Nations women equalities treaty, an academic has said.
Jackie Jones, law professor at the University of the West England, said there could be legal grounds for the state pension age hike for women to be removed and for full restitution.
Ms Jones made her argument in a support document to a judicial review brought by BackTo60, a group supporting women affected by these changes, which is seeking to force the government to reverse its decision.
She wrote: "In general terms, the mechanisms chosen and their consequent negative impact on women born in the 50s breach the UK’s international law obligations."
This was under the Convention on the Elimination of all Forms of Discrimination Against Women (CEDAW), according to Ms Jones.
Described as an international bill of rights for women, the international treaty was adopted in 1979 by the United Nations General Assembly, instituted in 1981, and ratified by 189 states.
Ms Jones said the mechanisms used by the government and their impact constituted "discrimination against women and a failure on the part of the state to the advance women’s position in society as well as a state failure to implement substantive and/or transformative equality".
She stated the UK could have breached a number of articles under CEDAW, and had thereby put women affected "into a worse position, rather than advancing the position of women, causing severe hardship and health issues for women so affected".
She added: "The effect of the mechanisms in issue in this case have a discriminatory effect on women born in the 50s, adversely impacting on older women’s health, economic and social life.
"The voluntary use of the mechanisms have the effect of failing to provide adequate access to pensions for women and therefore must be removed and full restitution substituted."
When these points were put to the Department for Work & Pensions, they declined to comment.
The BackTo60 movement, which claims to have 723,500 supporters, is being supported by a legal team led by Michael Mansfield QC, renowned civil rights barrister, and legal firm Birnberg Peirce.
Backto60, along with other campaign groups like Women Against State Pension Inequality (Waspi), is arguing against the perceived 'inequality and unfair treatment' of women born in the 1950s who have experienced changes to their state pension age.
The groups claim that when the 1995 Conservative government's Pension Act included plans to increase the women’s state pension age to 65 – the same as men's – the changes were implemented unfairly, with little or no personal notice.
The movements also claimed the changes were implemented faster than promised with the 2011 Pension Act, and left women with no time to make alternative plans, leading to devastating consequences.
Backto60 is requesting the state pension age to be kept at 60 for women born in the 1950s, but such a decision would cost £77bn and has previously been dismissed by the government.